Images Dated 4th March 2005

Trichinipoly

The city of Trichinipoly (later Tiruchchirappalli or Tiruchirapalli) in southern India, circa 1866. In the background is the historical Rock Fort, containing 7th-century Pallava cave temples, a 17th-century fort, and a temple to Vinayaka (Ganesh). (Photo by Samuel Bourne/Hulton Archive/Getty Images)

© 2004 Getty Images

Canis Major constellation

Canis Major constellation. Optical image of the constellation Canis Major, the great dog. North is at top. At upper right is Sirius (Alpha Canis Majoris), the brightest star in the sky. It is a white star which lies only 8.6 light years from Earth. At bottom right is the second brightest star in the sky, Canopus (Alpha Carinae), in the constellation Carina, the keel. Canopus lies around 72 light years from Earth. To the left of Canis Major and Carina is the faint constellation Puppis, the poop deck. The Milky Way is seen running from top right to bottom left. This band of light is formed from the millions of stars in the plane of our galaxy

© ECKHARD SLAWIK/SCIENCE PHOTO LIBRARY

Capacitors

Capacitors. Assortment of capacitors of different sizes, shapes and magnitudes. Capacitors are used to store electric charge. They consist of two metal plates separated by a dielectric (non conducting, separating material). When connected to an electric current one plate receives electrons from the current, the other plate loses electrons to the current. This will happen until the charge on the plates is in equilibrium with the potential difference in the circuit, and current stops flowing. If the source of the potential difference (ie. a battery) is removed, then the capacitor will discharge through the circuit in the opposite direction

© ANDREW LAMBERT PHOTOGRAPHY/SCIENCE PHOTO LIBRARY